Garage Door Opener Starts Then Reverses

Reverses on its own.
Garage door opener starts then reverses. There may be two nuts on one track. When the opener is activated the screw rotates causing the nut to move until it reaches the switch. If the garage door only travels down an inch or so before reversing something is probably blocking the beam between the two safety sensors at the bottom of the rails or the sensors aren t aligned. It goes partway down reverses direction and goes back up again.
By wade shaddy updated december 19 2018 you push the button to close the garage door. This is almost always the result of a dirty. One for the opening limit and one for the closing limit. I have a garage door opener stanley d1000 a07 date 98523 i hit the wall button or remote button and it hums starts to move then stops and reverses itself then stops.
When the opener reverses the screw turns the opposite way and the nut travels back. This happens from both the read more. The 2 nd cause is the closing force could be set too light and the normal tension of the closed position exceeds what the door believes to be allowable tension.